This is my standard advice for first works, except that rare case where one has spent years researching and writing some definitive volume about a highfaluting or scholarly subject.

You want to get your feet wet. Go with the mechanism that gets that done quickly but in a "most excellent" and impressive fashion. You want to be able to point to your work with pride at the way it looks and reads. Don't worry about the money. Sure over a few thousand dollars profit, you want your share.
Also don't sign your self over as an indentured servant for 20 years or until the end of your natural life.